Overall Green alert Tropical Cyclone for LEE-23
in Canada, United States

Event summary

Tropical Cyclone LEE-23 can have a low humanitarian impact based on the maximum sustained wind speed, exposed population and vulnerability.

GDACS ID TC 1001008
Name LEE-23
From - To 05 Sep - 17 Sep
Exposed countries Canada, United States
Exposed population 1.1 million in Category 1 or higher
Maximum wind speed 269 km/h Category 5
Maximum storm surge 1.6 m (16 Sep 18:00 UTC)
Vulnerability Low (Canada)

GDACS Score

For more info on GDACS alert score click here.
Wind Storm surge Rainfall GDACS score
GDACS NOAA 74 km/h 1.6 m n.a. 0.5
Single TC: maximum expected impact (wind, storm surge, rainfall)
HWRF 266 km/h 1.6 m 768 mm 0.5
GFS 176 km/h n.a. 625 mm 0.5
ECMWF 115 km/h 2.6 m 790 mm 0.5
Maximum expected impact (wind, storm surge and rainfall) using different data sources.
Virtual OSOCC
Meteo assessment
Satellite products
Analytical products
United States, Canada - Tropical cyclone LEE (ECHO 15 Sep 2023)Fri, 15 Sep 2023 10:25

  • A new tropical cyclone named LEE formed over the Atlantic Ocean on 5 September and started moving north-west toward north-eastern USA and the neighbouring suth-eastern Canada. On 15 September at 6.00 UTC, its centre was located over the Ocean approximately 750 km east of North Carolina coast and 1,150 km south of the Maine coast, with maximum sustained winds of 140 km/h (hurricane).
  • LEE is forecast to continue northward over the Ocean, slightly weakening, and it is expected to make landfall in the area between Maine (USA) and Nova Scotia Province (Canada) on the very early morning of 17 September (UTC), with maximum sustained winds of 110 km/h (tropical storm).
  • Heavy rainfall, strong winds and storm surge are forecast over Maine and Nova Scotia on 16-17 September. NOAA has issued an hurriane watch over this area. Preparedness activities are already ongoing by the Federal Emergency Management Agency (FEMA).
United States, Canada - Tropical cyclone LEE, update (ECHO 18 Sep 2023)Mon, 18 Sep 2023 10:45

  • Tropical cyclone LEE passed close to the north-eastern coast of USA and made landfall on 16 September over Nova Scotia Province (eastern Canada), moved north-east and crossed Newfoundland Island on 18 September. After that, it moved across the North Atlantic Ocean, weakening and dissipating. 
  • According to media reports, one person died in Maine State, north-eastern USA, due to a severe weather-related incident, around 120,000 people were without power on 16 September in Nova Scotia as well as 50,000 others in Maine as winds knocked down trees and power lines.
  • For the next 24 hours, moderate to heavy rainfall is forecast over the north-eastern USA and eastern Canada.
Detailed event map. European Union, 2024. Map produced by EC-JRC.
The boundaries and the names shown on this map do not imply official endorsement or acceptance by the European Union.

Updates on volcanic activity (Smithsonian)

Latest media headlines

Articles: 207 | About casualties: 1 | Last hour: 0

Tropical Storm Lee forms in Atlantic, forecast to become major hurrica ... 2023-09-06T11:56+0200.

SAN JUAN, Puerto Rico — Tropical Storm Lee formed Tuesday in the Atlantic Ocean and was forecast to become a major hurricane as it approaches the Caribbean by the weekend, forecasters said. The storm was located some 1,230 miles (1,980) kil
...(more)
NEXT Weather: Tropical Storm Lee expected to intensify into dangerous ... 2023-09-06T11:48+0200.

MIAMI - The CBS News Miami NEXT Weather team is tracking Tropical Storm Lee which is near hurricane strength in the tropical Central Atlantic. Tropical Storm Lee 9/6/2023 5AM NEXT Weather. The National Hurricane Center expects Lee to rapidl
...(more)
Tropical Storm Lee forecast to become major hurricane as it heads to t ... 2023-09-06T11:47+0200.

SAN JUAN, Puerto Rico (AP) - Tropical Storm Lee formed Tuesday in the Atlantic Ocean and was forecast to become a major hurricane as it approaches the Caribbean by the weekend, forecasters said. The storm was located some 1,230 miles (1,980
...(more)
Warm Wednesday with strong storms likely for Metro Detroit2023-09-06T11:45+0200.

4WARN WEATHER – A mild and muggy morning once again under mostly cloudy skies with temperatures starting around 70 degrees. SUNRISE: 7:04 A.M. Warming up again this Wednesday afternoon as we top out in the mid-80s early ahead of a cold fron
...(more)

Estimated casualties (PAGER)

USGS estimates the number of casualties for each earthquake for the Prompt Assessment of Global Earthquakes for Response (PAGER) product.
The graph shows the current fatalities estimate.

Exposed population

Data, images, links, services and documents

For this events, GDACS has links to information from the following sources: EC-JRC (40), (2), WMO (1), INFORM (2),